He rammed the moped last November in Erith, south east London, causing the rider to suffer a broken foot and head injuries. He was not wearing a helmet.

The 17-year-old was then arrested and admitted attempted theft, but the Independent Office for Police Conduct (IOPC) began to investigate whether the officer had “proper authorisation” to knock the teen off the bike.

The IOPC is expected to decide within weeks whether to recommend the policeman is prosecuted.

'It's necessary'

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Mr Hobbs said he thought the public were largely in favour of the ramming tactic.

“It’s necessary - these individuals ride around recklessly, often the bikes are stolen, they can inflict terrible damage on people including murdering them,” he said.

“They cause injuries and trauma, the whole thing was getting out of control.”

Moped crime figures in London were down 36% between January and October this year compared to 2017, and Mr Hobbs said the borough of Camden had reduced the moped crime rate by 90% since knocking offenders off their bikes.